1. Field of the Invention
This invention relates to a spray head having a spray nozzle that provides a wobbling motion.
2. Background of the Related Art
Showerheads are commercially available in numerous designs and configurations. While many showerheads are designed and sold for their decorative styling, there is a great number of different showerhead mechanisms which are intended to improve or change one or more characteristic of the water spray pattern. Any particular spray pattern may be described by the characteristics of spray width, spray distribution or trajectory, spray velocity, and the like. Furthermore, the spray pattern may be adapted or designed for various purposes, including a more pleasant feeling to the skin, better performance at rinsing, massaging of muscles and conservation of water, just to name a few.
The vast majority of showerheads may be categorized as being either stationary or oscillating and having either fixed or adjustable openings or jets. Stationary showerheads with fixed jets are the simplest of all showerheads, consisting essentially of a water chamber and one or more jets directed to produce a constant pattern. Stationary showerheads with adjustable jets are typically of a similar construction, except that some adjustment of the jet direction, jet opening size and/or the number of jets utilized. For example, a showerhead typically used in new residential home construction provides a stationary spray housing having a plurality of spray jets disposed in a circular pattern, wherein the velocity of the spray is adjustable my manually rotating an adjustment ring relative to the spray housing.
These stationary showerheads cause water to flow through its apertures and contact essentially the same points on a user's body in a repetitive fashion. Therefore, the user feels a stream of water continuously on the same area and, particularly at high pressures or flow rates, the user may sense that the water is drilling into the body, thus diminishing the positive effect derived from such a shower head. In order to reduce this undesirable feeling, various attempts have been made to provide oscillating showerheads.
Examples of oscillating showerheads are disclosed in U.S. Pat. No. 3,791,584 (Drew et al.), U.S. Pat. No. 3,880,357 (Baisch), U.S. Pat. No. 4,018,385 (Bruno), U.S. Pat. No. 4,944,457 (Brewer), and U.S. Pat. No. 5,577,664 (Heitzman). U.S. Pat. No. 4,944,457 (Brewer) discloses an oscillating showerhead that uses an impeller wheel mounted to a gear box assembly which produces an oscillating movement of the nozzle. Similarly, U.S. Pat. No. 5,577,664 (Heitzman) discloses a showerhead having a rotary valve member driven by a turbine wheel and gear reducer for cycling the flow rate through the housing between high and low flow rates. Both of these showerheads require extremely complex mechanical structures in order to accomplish the desired motion. Consequently, these mechanism are prone to failure due to wear on various parts and mineral deposits throughout the structure.
U.S. Pat. No. 3,791,584 (Drew et al.) also discloses an oscillating showerhead, but utilizes a nozzle mounted on a stem that rotates and pivots under forces places on it by water entering through radially disposed slots into a chamber around stem. Although this showerhead is simpler than those of Brewer and Heitzman, it still includes a large number of piece requiring precise dimensions and numerous connections between pieces. Furthermore, the showerhead relies upon small openings for water passageways and is subject to mineral buildup and plugging with particles.
U.S. Pat. No. 5,467,927 (Lee) discloses a showerhead with a turbine having a plurality of blades designed to produce vibration and pulsation. One blade is provided with an eccentric weight which causes vibration and an opposite blade is provided with a front flange which cause pulsation by momentarily blocking the water jets. Again, the construction of this showerhead is rather complex and its narrow passageways are subject to mineral buildup and plugging with particulates.
U.S. Pat. No. 5,704,547 (Golan et al.) discloses a shower head including a housing, a turbine and a fluid exit body, such that fluid flowing through the turbine causes rotation of the turbine. The rotating (spinning) turbine can be used to cause rotation of the fluid exit body and/or a side-to-side rocking motion in a pendulum like manner.
U.S. Pat. No. 4,073,438 (Meyer) discloses a sprinkler head having a housing with an inlet, a water distributing structure having a nozzle on one end and a cup shaped element at the opposite end which is operative in response to the tangential flow of water into the housing for effecting the orbital movement of the nozzle. There is also disclosed a disk that rotates in rolling contact with a surface within the housing for effecting the fractional rotation of the nozzle. The cup shaped element rotates about the longitudinal axis in response to the flow of water from the inlet.
A particularly useful action for a showerhead is referred to as "wobbling." The term "wobbling" may be defined as the motion of a circular member rolling on its edge along a surface following a circular path. A common example of wobbling is what occurs when a coin is spun on its edge over a smooth surface. The coin begins spinning or rotating in an vertically upright position, but as the coin slows, the coin begins to wobble along a circular path having an ever increasing diameter until the coin comes to rest on its face. While a wobbling motion will often be accompanied by some degree of rotation, a wobbling member will have points on its surface which experience a sequence of up and down motions as well.
Referring to FIG. 1, U.S. Pat. No. 3,091,400 (Aubert) discloses a dishwashing machine having a rotary wobble spraying apparatus comprising a spraying body having a spraying head and a bearing piece, together with a ring surrounding it. The wobble spraying apparatus 10 comprises body piece 12, having a spraying head 14 attached thereto, and a ring 16 surrounding it. The body piece 12 has an internal conical bearing seat 18 and is placed on a water supply pipe 20 having a rounded edge forming a bearing seat 22. The extending piece 12 has a collar 24 pulled down over the supply pipe 20 and an adjoining, outwardly projecting shoulder 26 engages the lower side of ring 16 and rolls on it when water is supplied under pressure. Water supplied through pipe 20 enters a distribution chamber 28 and emerges through the spraying apertures 30 of spraying head 14. The orientation of the apertures 10 is chosen so that a moment of momentum set the spraying body into rotation, whereby the shoulder 26 of body 12 rolls on the ring 16 as indicated at point 32.
A primary disadvantage of Aubert is that the wobbling motion is caused by the tangential orientation of the apertures in the spray head, thereby limiting the choice of spray patterns. Specifically, the tangential apertures will form a very wide spray pattern that may be useful for dishwashing, but is very undesirable for a showerhead. Furthermore, because of the mass of the spray head 14 and the annular contact between the shoulder 26 and the ring 16, the water supply must be run at a high velocity and pressure before the spray head will begin wobbling.
Therefore, there is a need for an improved spray head or showerhead that delivers water in a uniform fashion such that the droplet path for any given aperture is continually changing over time. It would be desirable if the spray head were able to deliver water in the desired manner, even at low pressures of flow rates dictated or desirable for water conservation. It would be further desirable if the spray head provided a simple design and construction with minimal restriction to water flow.